Certain medicines which must be administered to patients by injection consist of lyophilized powder dissolved in a diluent. The powder and diluent must be mixed together immediately before use, since if the powder and diluent are mixed at an earlier time, the medicine will deteriorate rapidly.
Conventionally the powder and diluent are mixed at time of dosage and the medicine is transferred into a syringe for immediate subsequent injection.
The present invention is directed toward a new type of medical device wherein the powder and diluent can be stored in separate sealed chambers of an integral unit for indefinite periods and wherein the unit itself can be disposed either in a mixer for immediate mixing and transfer to a syringe or in a syringe wherein mixing can ensue immediately before injection.